As smaller transistors are manufactured, the critical dimension (CD) or resolution of patterned features is becoming more challenging to produce. Self-aligned patterning needs to replace overlay-driven patterning so that cost-effective scaling can continue even after extreme ultraviolet lithography (EUV) introduction. Patterning options that enable reduced variability, extend scaling and enhanced CD and process control are needed. Selective formation of thin films is a key step in patterning in highly scaled technology nodes.